At present, common heat supply system employs coal, gas or oil as main energy resources. It is known that not only do coal, gas and oil have limited reserves, but produce massive ash, dust or exhaust gas while/after their combustion, not only polluting the environment, but transforming the atmosphere properties, thus resulting in greenhouse effect which warms the earth and then melts glaciers and rises the ocean level and etc. Energy used in conventional refrigerating systems is electricity, which costs higher, and an amount of it are also generated from burning fuels like coal, gas or oil etc, therefore the same problems caused by combusting those fuels to the environment happen here again. However, massive low level cold and heat resources are stored in underground water. A water-water heat pump system produced by CiAT Co., Ltd. uses well water as energy resource, however two wells are required for this system, one is for water supplying, and the other is for water returning. Consequently, the cost is high.